Carrier for forward edge of extendible and retractable flexible sheet



Sept. 20, 1966 J. H. LAMB CARRIER FOR FORWARD EDGE OF EXTENDIBLE AND RETRACTABLE FLEXIBLE SHEET 2 SheetsSheet 1 Filed Aug. 7, 1961 INVENTOR. JOE H. LAMB m ATTORNEYS Sept. 20, 1966 J. H. LAMB 3,273,171

CARRIER FOR FORWARD EDGE OF EXTENDIBLE AND RETRACTABLE FLEXIBLE SHEET Filed Aug. 7, 1961 2 Sheets-Sheet 2 A (Q 11 n wIIII llllIII/l 1 INVENTOR. JOE H. LAMB ATTORNEYS United States Patent 3,273 171 CARRIER FOR FORWARD EDGE OF EXTENDIBLE AND RETRACTABLE FLEXIBLE SHEET Joe H. Lamb, Salt Lake City, Utah, assignor, by mesne assignments, to Cover-Pools Incorporated, Salt Lake City, Utah, a corporation of Utah Filed Aug. 7, 1961, Ser. No. 131,049 18 Claims. (Cl. 4-172) This invention relates to apparatus for extending and retracting a sheet of flexible material relative to an area to be protectively covered, for example a swimming pool when not in use.

The invention is particularly concerned with providing an effective carrier for the forward margin of such a flexible sheet in order to facilitate extension and retraction of the sheet and entry of its forward edge in a receiving strip when the sheet is in its fully extended position as a protective cover.

In my copending patent application Serial No. 30,493, filed May 20, 1960, since abandoned and entitled, Rolled Sheet Extending and Retracting Apparatus," I disclose in detail an extendible and retractable cover for swimming pools wherein an impervious cover sheet of flexible material is rolled on a drum or roller at one end of the pool and is adapted to be unrolled and extended over the pool area to cover same when the pool is not in use. The longitudinal edges of the sheet are thickened or beaded to serve as anchoring slides with respect to slideway strips secured along the longitudinal margins of the pool. Special mechanism and structural components are utilized in conjunction with the drum for unrolling and for re-rolling the cover sheet.

As disclosed in that application, the forward edge of the cover sheet is supported and carried by structure conforming to the broader aspects of the present invention. Thus, the forward edge of the flexible cover sheet is secured to a rigid carrier strip having shaft members protruding from its opposite ends and wheels freely rotatable on such shaft members. The strip is advantageously of aluminum, extruded to provide a re-entrant slideway channel along the rearward margin of the strip for receiving and anchoring a thickened or beaded forward edge portion of the cover sheet, and, also, to form a hollow cylindrical portion with forwardly protruding lip along the forward margin of the strip. The shaft members protrude from the hollow cylindrical portion and serve to mount carriage wheels. These wheels ride along the deck marginal to the pool, and the forwardly protruding lip is received by a terminal strip which extends marginally of that end of the pool lying opposite to the rolled cover sheet.

The present application is a continuation in part of my aforesaid application Serial No. 30,493.

As stated in that application and as a feature of the invention, enough slack is provided in the cover sheet to permit it to float on the surface of the water in the pool. In this way there is no significant frictional resistance to extension and retraction of such sheet, because it is effectively supported intermediate its margins on what may be regarded as a lubricant surface and there is no undue pull on the cover beads in their slideway channels.

However, with pools of odd, non-rectilinear configuration, such as kidney shape, a portion of the pool deck necessarily underlies the cover sheet, and, unless the forward margin thereof is raised during extension and retraction, there is harmful dragging and abrasion of same as well as interference with movement.

One of the objects in the making of the invention, therefore, was to provide for raising the forward margin of the cover sheet during extension and retraction.

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This is accomplished by utilizing ofrset axles for the carriage wheels and an arrangement for maintaining the offset portions of these axles raised during extension and retraction of the cover sheet.

An object with respect to extendible and retractable covers for pools of any shape was to provide a relatively rigid yet visually attractive leading edge for the cover sheet.

This is accomplished by providing a strip having a re-entrant slideway channel along its rear marging for receiving and anchoring a thickened edge or bead provided along the forward edge of the cover sheet, and by providing a tubular portion along the forward margin of the strip with a sealing or closure lip extending along the forward part of such tubular portion for mating engagement with a strip secured along the end of the pool at the termination of the extension stroke of the cover sheet.

Another object was to employ a flexible cover sheet without the need for structural reinforcement intermediate its margins, this being accomplished by leaving enough slack across the width of the sheet between anchoring slideway and guide channels to permit such sheet to float on the surface of the water in the pool.

There are illustrated in the accompanying drawings specific embodiments of the invention representing what are presently regarded as the best modes of carrying out the generic concepts in actual practice.

In the drawings:

FIG. 1 represents a top plan view of a kidney shaped swimming pool equipped with the extendible and retractable cover apparatus of my aforementioned copending patent application and with a form of carrier for the forward edge of the cover sheet which conforms to the present invention;

FIG. 2, a fragmentary view partly in elevation and partly in vertical section taken from the standpoint of line 22, FIG. 1 and drawn to a larger scale;

FIG. 3, a fragmentary view in top plan corresponding to the right hand portion of FIG. 1 but with the cover completely extended;

FIG. 4, a fragmentary elevation taken from the standpoint of line 44, FIG. 3 and drawn to the scale of FIG. 2;

FIG. 5, a view partly in vertical section and partly in front elevation taken from the standpoint of line 55, FIG. 2, but drawn to a somewhat larger scale;

FIG. 6, a fragmentary vertical section taken on the line 6-6, FIG. 3, and drawn to the scale of FIGS. 2 and 4;

FIG. 7, a view corresponding to the sectional portion of FIG. 5, but taken with the cover in the fully extended position of FIGS. 3 and 4 and illustrating a somewhat different form of the invention;

FIG. 8, a similar view, but taken with the cover in the intermediate position of FIGS. 1, 2, and 5;

FIG. 9, a view corresponding to that of FIG. 2, but showing another form of the invention;

FIG. 10, a view corresponding to that of FIG. 4, but with respect to the embodiment of FIG. 8; and

FIG. 11, a fragmentary horizontal section taken on the line 1111, FIG. 9.

Referring to the drawings:

A kidney-shaped swimming pool 15 having a marginal deck 16 is provided with an extendible and retractable, sheet cover 17 of flexible material, such as a vinyl plastic, which is slideably anchored along its lateral margins in slideway strips 18 defining a rectilinear path of travel for such cover sheet.

Cover sheet 17 is rolled in conformity with my aforementioned patent application Serial No. 30,493. The operating mechanism for extending and retracting such cover sheet is housed in covered box 19, either as disclosed in that application or in my copending application Serial No. 126,130, filed July 24, 1961, since matured into Patent No. 3,076,975, dated Feb. 12, 1963, and entitled Protectively Housed, Extendible and Retractable C-over Apparatus for Swimming Pools.

Although the cover sheet is thickened, i.e. provided with beads 17a along its respective lateral edges as in my aforesaid applications, it is made with suflicient slack along its width to hang down and float upon the water 20, FIG. 6, in the swimming pool. This means that such cover sheet is well supported intermediate its margins and that the beads 17a slide freely and easily within and along slideway channels 18a of the strips 18.

As is the case in my aforesaid patent applications, the forward edge of the cover sheet 17 is thickened, i.e. pro vided with a bead 17b, FIGS, 2 and 6, and is slideably received by a re-entrant channel member 21a formed along the rearward margin of a relatively rigid carrier strip 21, which is preferably extruded aluminum. Such strip 21 is provided along its forward margin with an open-ended, tubular portion 2112, which has a forwardly protruding lip 21c extending along its length. Such tubular portion 21b serves both to structurally strengthen and stiffen the strip and, in appropriate instances, to journal carriage axles in a manner hereinafter described. To give additional stiffness in instances of exceptionally wide pools, internally projecting fins 21e such as are shown in connection with the embodiment of FIGS. 7 and 8 and as described hereinafter may be additionally provided in tubular portion 2111 as integral parts of the extrusion. The intermediate portion 21c of the strip is made as wide as deemed proper for both strip stiffness and visual attractiveness in individual instances, and may be flat, as shown, or of any other suitable contour.

It is desirable to raise the leading edge and forward margin of the cover sheet during extension and retraction of such sheet, both to guard against interference with movement and to avoid wear. In accordance with the invention a pair of offset axles 22 is provided for this purpose, the individual axles having shaft portions 22a, FIG. 5, journaled in opposite ends of the tubular portion 21b of leading edge strip 21 as by means of bearing blocks 23, which are held in place in any suitable manner, for example by screws 24. These axles project outwardly from the strip 21 and include offset portions 22b which terminate in outwardly projecting spindles 22c offset from but parallel with the journaled shaft portions 22a. Rotatably mounted on spindles 22c are respective wheels 25, which preferably ride on the pool deck 16 but which could be made to ride directly on the slideway strips 18.

Means are provided for keeping leading edge strip 21 in raised position once it has been lifted manually -to raise the offset portions 22b of the axles as shown in FIGS. 2 and 5. Such means can take the form of elongate flat or leaf springs 26. Conveniently a pair of same is located at respectively opposite lateral sides of the sheet, FIG. 1, near the beads 17a, with forward ends riveted to leading edge strip 21 and rearward ends riveted directly to the cover sheet, as shown, the springs being preferably precurved somewhat as illustrated in FIG. 2. Coil springs 27, FIG. 5, encircle shaft members 22a of'the respective axles, being anchored to the strip at one end and to the shaft member at the other end, as shown, to resiliently bias offset portions 22b of such axles forwardly, see FIG. 2. These springs are tensioned by manually rotating the respective axles counterclockwise as many times as required for proper performance.

In the embodiment of FIGS. 7 and 8, the means for keepingleading edge strip 21 in raised position comprises a pair of keeper notches 30, the individual notches being formed at opposite ends, respectively, of the tubular portion 21b of such strip 21 for receiving and engaging-see FIG. 8-the offset portions 31b of the respective axles 31 wh n y are m n lly turned to a raised position such as that shown in FIG. 2. For retaining the axles in this raised position during travel of the carrier strip 21, coil compression springs 32 are interposed between the respective bearing blocks 33 and ends of the shaft members 31a of the respective axles. Nut and washer assemblies 34 are fastened to the ends of the respective shaft members 31a as abutments for springs 32.

In the embodiment of FIGS. 9-11, the means for keeping carrier or leading edge strip 21 in raised position comprises a pair of offset axles 40 and wheels 41, the individual axles of the pair being journaled in respective bearing blocks 42, while the means for retaining such axles in raised position comprises a second and similar pair of axles 43 and wheels 44, the individual axles of which are journaled in respective bearing blocks 42 similarly and in juxtaposition to the individual axles 40. Cotter pins 45, FIG. 11, or other suitable means hold the axles in position in the bearing blocks, while respective lengths 46 of subst-antially non-stretchable material, such as link chain, serve to hold the respective sets of axles at opposite ends of the carrier strip in-mutually spread condition, as shown in FIG. 9.

The height at which carrier strip 21 is kept can be adjusted by changing the extent of spread of the two axles 40 and 43 of each set, this being made possible in the illustrated construction by providing respective hooks 47 as the means by which the chains are fastened to one of the spread axles of the sets.

Forwardly protruding lip 21c of the carrier strip is provided as a sealing member for use at the termination of the extension stroke of the cover sheet. To this end, a terminal strip 50, FIGS. 1 and 3, is secured in position bordering that end of the pool which lies opposite the end at which box 19 is positioned. Such strip 50 is preferably formed similarly to slideway strips 18 and preferably provides a continuation thereof, as shown. Its slideway channel 19a, FIG. 6, serves to receive lip 21c when cover sheet 17 is fully extended and to more or less seal such sheet in its extended, protective position over and with respect to swimming pool 15.

In all instances, internally projecting fins 21e, FIGS. 7 and 8, may be formed integrally with tubular portion 21b during extrusion, and reamed from the opposite ends to accommodate the bearing blocks.

Whereas there are here specifically illustrated and described certain embodiments which we presently regard as the best modes of carrying out the invention, it should be understood that various changes may be made without departing from the inventive concepts particularly pointedout and distinctly claimed herebelow.

I claim:

1. In combination, a horizontally disposed sheet of flexible material; stationary means at one end of said sheet for extending and retracting the sheet relative to a horizontal area to be protectively covered thereby; a relatively rigid, traveling strip at the other end of said sheet extending along and secured to the sheet as a forward margin thereof; a pair of offset axles, the individual axles of which are journaled in opposite ends of the strip, respectively, and have respective offset portions extend-ing outwardly therefrom, with respective spindle ends offset from but parallel with the journaled portions of said axles, so that said strip can be raised for travel; a pair of wheels, the individual wheels of which are journaled on said spindle ends, respectively, and are adapted to ride adjacent said area to be covered during travel of said strip; and means for retaining said strip in raised position during extending and retracting movement of strip and sheet following raising said strip with respect to said wheels.

2: The combination set forth in claim 1, wherein the strip-retaining means comprise elongate leaf springs, the individual springs of which extend substantially normal to the strip and are secured to said strip adjacent their forward ends and to the cover adjacent their rearward ends; and resilient means normally biasing the olfset portions of the axles forwardly.

3. The combination set forth in claim 2, wherein there is a pair of the leaf springs, the individual springs of which are located near opposite lateral edges of the sheet and opposite ends of the strip, respectively.

4. The combination set forth in claim 2, wherein the biasing means comprise coil springs encircling the journaled portions of the axles, respectively, and each having one end anchored to the strip and one end anchored to the axle.

5. The combination set forth in claim 1, wherein the strip-retaining means comprises a pair of keepers associated with the strip at predetermined locations such as to engage portions of the respective axles when the strip is raised, said axles being mounted for movement into and out of engaging positions; and means for retaining said axles in their engaging positions.

6. The combination set forth in claim 5, wherein the keepers are respective notches in the ends of the strip, the axles being movable into and out of said notches along their journal axes when the strip is in a predetermined raised position; and wherein the axle-retaining means are springs normally biasing the respective axles inwardly of said strip along said journal axes.

7. The combination set forth in claim 1, wherein the strip-retaining means comprise an additional pair of olfset axles and an additional pair of wheels mounted similarly to the first and in juxtaposition thereto; and means for retaining the axles of each set in mutually spread positions at respectively opposite, longitudinal sides of the strip.

8. The combination set forth in claim 7, wherein each axle-retaining means is a length of flexible but substantially non-stretchable material connected adjacent its ends to the respective spread axles to prevent them from spreading further.

9. The combination set forth in claim 1, wherein the strip secured to and forming the leading margin of the sheet is formed as a structural extrusion of rigid material having a longitudinally slotted, tubular, slideway channel portion extending along one of its longitudinal margins; a longitudinally closed, tubular portion extend ing along the other longitudinal margin of the strip in spaced relationship to said slideway channel; and a web member interposed between said slideway portion and said tubular portion, the sheet having its forward edge thickened as a bead and slidably received by and anchored within said channel; and wherein the axles are journaled within and extend from opposite ends, respectively, of said tubular poriton.

10. The combination set forth in claim 9, wherein a terminal strip is secured in position bordering the area to be covered and extending along the termination of the extension stroke of the sheet, said strip having a relatively narrow channel defined along its length; and wherein the leading edge strip of the cover sheet includes a sealing lip projecting forwardly from and extending therealong, said lip being adapted to enter said channel at the termination of said extension stroke of the sheet.

11. The combination set forth claim 9, wherein the strip secured to and forming the leading margin of the sheet includes stiffening fins projecting inwardly of and extending along the interior of the tubular portion.

12. A structural extrusion of rigid material, comprising a strip having a longitudinally slotted, tubular, slideway channel portion extending along one of its longitudinal margins for receiving the beaded edge of a sheet of flexible material; a longitudinally closed, tubular portion extending along the other longitudinal margin of the strip in spaced relationship to said slideway channel; and a web member interposed between said slideway portion and said tubular portion.

13. The structural extrusion of claim 12, wherein an outwardly projecting lip extends along the tubular portion.

14. The structural extrusion of claim 12, wherein there are stifiening fins projecting inwardly of and extending along the interior of the tubular portion.

15. In combination with a swimming pool, a cover of flexible sheet material disposed at and along one end of the pool for extension and retraction with respect to said pool, the cover sheet having its longitudinal edges thickened as slides; slideway strips secured along the longitudinal margins of the pool and having re-entrant slideway channels which slidably receive said thickened edges of the cover sheet and anchor them laterally of the pool, said cover sheet having slack across its width sufiicient to permit it to float on the surface of the water in the pool; means for extending and retracting said cover sheet; and a relatively rigid strip secured to and along the forward margin of said cover sheet as the leading edge thereof.

16. The combination set forth in claim 15, wherein liftable and depressible carriage means are associated with the leading edge of the cover sheet for raising it during extension and retraction and for lowering it when desired.

17. The combination set forth in claim 15, wherein a terminal strip is secured in position bordering the other end of the pool and extending along the termination of the extension stroke of the sheet, said strip having a relatively narrow channel defined along its length; and wherein the leading edge strip of the cover sheet includes a sealing lip projecting forwardly from and extending therealong, said lip being adapted to enter said channel at the termination of said extension stroke of the sheet.

18. The combination set forth in claim 17, including an elongate box housing the means for extending and retracting the cover sheet; said box having a hinged cover which normally bears down upon the sheet as it is extended and retracted relative to the box, the leading edge strip of the sheet being adapted to remain visually exposed outside said box at the termination of the retraction stroke.

References Cited by the Examiner UNITED STATES PATENTS 2,580,555 1/ 1952 Kroeger 4-172 2,861,277 11/ 1958 Hermann 4-172 2,914,776 12/ 1959 Hotz 4172 2,958,083 11/1960 Shook et a1 4172 2,980,921 4/1961 Bartolucci 4172 FOREIGN PATENTS 844,066 8/ 1960 Great Britain.

LAVERNE D. GEIGER, Primary Examiner.

FRANK E. BAILEY, FRANK H. BRONAUGH,

Examiners.

H. KLINKSIEK, Assistant Examiner. 

1. IN COMBINATION, A HORIZONTALLY DISPOSED SHEET OF FLEXIBLE MATERIAL; STATIONARY MEANS AT ONE END OF SAID SHEET FOR EXTENDING AND RETRACTING THE SHEET RELATIVE TO A HORIZONTAL AREA TO BE PROTECTIVELY COVERED THEREBY; A RELATIVELY RIGID, TRAVELING STRIP AT THE OTHER END OF SAID SHEET EXTENDING ALONG AND SECURED TO THE SHEET AS A FORWARD MARGIN THEREOF; A PAIR OF OFFSET AXLES, THE INDIVIDUAL AXLES OF WHICH ARE JOURNALED IN OPPOSITE ENDS OF THE STRIP, RESPECTIVELY, AND HAVE RESPECTIVE OFFSET PORTIONS EXTENDING OUTWARDLY THEREFROM, WITH RESPECTIVE SPINDLE ENDS OFFSET FROM BUT PARALLEL WITH THE JOURNALED PORTIONS OF SAID AXLES, SO THAT SAID STRIP CAN BE RAISED FOR TRAVEL; A PAIR OF WHEELS, THE INDIVIDUAL WHEELS OF WHICH ARE JOURNALED ON SAID SPINDLE ENDS, RESPECTIVELY, AND ARE ADAPTED TO RIDE ADJACENT SAID AREA TO BE COVERED DURING TRAVEL OF SAID STRIP; AND MEANS FOR RETAINING SAID STRIP IN RAISED POSITION DURING EXTENDING AND RETRACTING MOVEMENT OF STRIP AND SHEET FOLLOWING RAISING SAID STRIP WITH RESPECT TO SAID WHEELS. 